Altering streaming video encoding based on user attention

ABSTRACT

Disclosed are various embodiments for adjusting the encoding of a video signal into a video stream based on user attention. A video signal is encoded into a video stream. A temporary lapse of attention by a user of the interactive application is predicted. The encoding of the video signal into the video stream is adjusted from an initial state to a conservation state in response to predicting the temporary lapse of attention by the user. The conservation state is configured to conserve one or more resources used for the video stream relative to the initial state.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of, and claims priority to, co-pendingU.S. patent application entitled “ALTERING STREAMING VIDEO ENCODINGBASED ON USER ATTENTION,” filed on Dec. 1, 2010, and assignedapplication Ser. No. 12/957,450, which is incorporated herein byreference in its entirety.

BACKGROUND

A video signal is typically encoded by one or more video encoders inorder to generate a video stream capable of being sent over a datacommunications network. Such encoding is useful to reduce the bitrateassociated with the video signal, thereby allowing the video stream tofit within the bandwidth constraints of the network. Data reduction isalso helpful in some systems to permit forward error correction data tobe transmitted in the video stream. However, video encoders may beresource intensive, sometimes requiring significant processing and/ormemory resources in order to achieve acceptable video quality.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present disclosure can be better understood withreference to the following drawings. The components in the drawings arenot necessarily to scale, emphasis instead being placed upon clearlyillustrating the principles of the disclosure. Moreover, in thedrawings, like reference numerals designate corresponding partsthroughout the several views.

FIG. 1 is a drawing of a networked environment according to variousembodiments of the present disclosure.

FIGS. 2A-2C are drawings of user interfaces rendered by a client in thenetworked environment of FIG. 1 according to various embodiments of thepresent disclosure.

FIGS. 3 and 4 are flowcharts illustrating examples of functionalityimplemented as portions of an encoding adjustment application executedin a computing device in the networked environment of FIG. 1 accordingto various embodiments of the present disclosure.

FIG. 5 is a schematic block diagram that provides one exampleillustration of a computing device employed in the networked environmentof FIG. 1 according to various embodiments of the present disclosure.

DETAILED DESCRIPTION

The present disclosure relates to adjusting the encoding of a videosignal into a video stream based on user attention or anticipated userattention. Given that a video stream may use significant encodingresources and/or network bandwidth resources, it may be desirable toreduce such resource consumption when a user is not paying attention tothe video stream. In some cases, it may be desirable to reduce suchresource consumption even when a user is not paying attention merely toa portion of a screen rendered from the video stream.

Various embodiments of the present disclosure adjust the encoding of avideo signal generated by an interactive application into a video streambased on the attention of the user. As a non-limiting example, a userwho is playing a game may leave the room temporarily or otherwise mightnot pay attention to a video stream that is encoded from a video signalgenerated by the game. Accordingly, a video encoder that encodes thevideo signal into the video stream may be adjusted to stop encoding orto reduce resource consumption during a temporary lapse of attention bythe user to the video stream.

As another non-limiting example, an event occurring in a portion of agame screen may draw the attention of the user and induce a saccade. Asaccade is a rapid movement of the eyes as they jump from fixation onone point to another. When a person shifts visual focus to somethingthat is moving, the person perceives a smooth visual experience.However, the actual physiology involved differs from the perception. Inreality, the eye unfocuses, the muscles controlling the eye aim the eyeto focus on another object, and the eye refocuses on the other object.

During this time, which may last approximately between 30 and 50milliseconds, the visual field is edited out by the brain, and the brainfills in the gap. If something unusual occurs in the visual field duringthe saccade, the user does not perceive it due to this saccadic maskingphenomenon. Accordingly, a video encoder that encodes the video signalof the game may be adjusted to reduce resource consumption while theuser is experiencing saccadic masking. In the following discussion, ageneral description of the system and its components is provided,followed by a discussion of the operation of the same.

With reference to FIG. 1, shown is a networked environment 100 accordingto various embodiments. The networked environment 100 includes one ormore computing devices 103 in data communication with one or moreclients 106 by way of a network 109. The network 109 includes, forexample, the Internet, intranets, extranets, wide area networks (WANs),local area networks (LANs), wired networks, wireless networks, or othersuitable networks, etc., or any combination of two or more suchnetworks.

The computing device 103 may comprise, for example, a server computer orany other system providing computing capability. Alternatively, aplurality of computing devices 103 may be employed that are arranged,for example, in one or more server banks or computer banks or otherarrangements. For example, a plurality of networked computing devices103 together may comprise a cloud computing resource, a grid computingresource, and/or any other distributed computing arrangement. Suchcomputing devices 103 may be located in a single installation or may bedistributed among many different geographical locations. For purposes ofconvenience, the computing device 103 is referred to herein in thesingular. Even though the computing device 103 is referred to in thesingular, it is understood that a plurality of computing devices 103 maybe employed in the various arrangements as described above.

Various applications and/or other functionality may be executed in thecomputing device 103 according to various embodiments. Also, variousdata is stored in a data store 112 that is accessible to the computingdevice 103. The data store 112 may be representative of a plurality ofdata stores 112 as can be appreciated. The data stored in the data store112, for example, is associated with the operation of the variousapplications and/or functional entities described below.

The components executed on the computing device 103, for example,include a server application 115, an encoding adjustment application116, a plurality of applications 118 a, 118 b . . . 118N, a plurality ofvideo encoders 119 a, 119 b . . . 119N, a plurality of wrappers 121 a,121 b . . . 121N, and other applications, services, processes, systems,engines, or functionality not discussed in detail herein. The serverapplication 115 is executed to launch applications 118, which may beexecuted within wrappers 121 that provide a virtualized environment.Although the principles of the present disclosure are illustrated withreference to applications 118 that are executed in remote servers, it isunderstood that the principles are applicable to any video stream thatdepicts saccade-inducing events or may be susceptible to userinattention. Non-limiting examples of such video streams may includemovies, television programs, televised sports programs, etc. Althoughgames are discussed herein as particular examples of applications 118,it is understood that the applications 118 may correspond to manydifferent types of interactive applications other than merely games invarious embodiments.

The server application 115 is executed to obtain input data 122 from theclients 106 and provide the input data 122 to the respective wrapper121. The server application 115 is also executed to send video data 123that is captured from the application 118 to the clients 106 as a videostream. The server application 115 may communicate with the client 106over various protocols such as, for example, hypertext transfer protocol(HTTP), simple object access protocol (SOAP), representational statetransfer (REST), real-time transport protocol (RTP), real time streamingprotocol (RTSP), real time messaging protocol (RTMP), user datagramprotocol (UDP), transmission control protocol (TCP), and/or otherprotocols for communicating data over the network 109. The serverapplication 115 is configured to maintain application state information124 associated with the executing applications 118.

The application 118 is an interactive application such as, for example,a game. The application 118 may be a single-player game, amultiple-player game, or include both single player and multiple playermodes. As non-limiting examples, the application 118 may correspond to afirst-person shooter game, an action game, an adventure game, a partygame, a role-playing game, a simulation game, a strategy game, a vehiclesimulation game, and/or other types of games. The application 118 may bea game originally designed for execution in a general-purpose computingdevice or in a specialized video game device such as, for example, avideo game console, a handheld game device, an arcade game device, etc.The application 118 may expect to access one or more resources of thedevice on which it is executed. Such resources may correspond to displaydevices, input devices, or other devices. In some cases, the application118 may request exclusive access to one or more of the resources,whereby no other applications may have access to the particularresources.

The video encoder 119 is able to encode a video signal generated by theapplication 118 into a video stream for transmission over the network109 to clients 106. The video stream may include an audio signalgenerated by the application 118 as well. To this end, the video encoder119 may include various types of video and audio encoders, such as, forexample, Moving Pictures Experts Group (MPEG) encoders, H.264 encoders,Flash® video encoders, etc. Such encoders may be selected according tofactors such as, for example, data reduction, encoding quality, latency,etc.

The video encoder 119 may introduce various encoding artifacts into thevideo stream that were not present in the video signal. Such encodingartifacts may comprise macroblocking, pixelation, “mosquito noise,”and/or other forms of encoding artifacts. The presence and severity ofthe encoding artifacts may depend on various factors, such as thecontent of the video signal, the maximum bitrate of the video stream,the data reduction approach employed by the particular video encoder119, etc.

In general, it may be the case that video encoders 119 that areconfigured to use lesser processing resources may produce video streamsof lower quality at a specified bitrate when compared to video encoders119 that are configured to use greater processing resources and producevideo streams at the same specified bitrate. Further, it may generallybe the case that video streams that are encoded at a lower bitrate havea lower quality than video streams that are encoded at a higher bitrate.Therefore, reducing consumption of resources such as processingresources and network bandwidth resources may result in lower qualityvideo streams.

The encoding adjustment application 116 is executed to detect periods ofuser inattention and to make adjustments to the corresponding videoencoder 119 to conserve one or more resources consumed by the videostream. For example, the encoding adjustment application 116 mayconfigure the video encoder 119 to stop encoding a video stream while auser is not paying attention to the rendered video stream.Alternatively, the encoding adjustment application 116 may configure thevideo encoder to encode the video stream using a lesser quality encodingto conserve resources while a user is not paying attention to therendered video stream.

In addition, the encoding adjustment application 116 may be executed todetect whether a rapid change is present in one or more frames of thevideo signal that is to be encoded. Such a rapid change may be predictedto draw the attention of the user to a region of the video frame wherethe rapid change is occurring, thereby inducing a saccade. In oneembodiment, the encoding adjustment application 116 may compare framesof the video signal to previous frames of the video signal to ascertainwhether a rapid change is present. In another embodiment, the encodingadjustment application 116 may be able to correlate frames of the videosignal to a profile of the application 118 that indicates whether arapid change is anticipated. In yet another embodiment, the encodingadjustment application 116 may obtain event indications from theapplication 118 that notify the encoding adjustment application 116 thata rapid change is anticipated.

The encoding adjustment application 116 may configure the video encoder119 to use lesser resources in encoding the video stream when asaccade-inducing event is present in the video signal. Because theattention of the user is drawn to the region of rapid change, otherareas of the video signal may be encoded to use less data, lessprocessing time, etc. for the duration of the saccade-inducing event.Such an event may last, for example, two to three frames, 30 to 50milliseconds, or some other duration. In one embodiment, the entirevideo frame may be encoded with a lesser quality encoding for at least aportion of the duration of the saccade-inducing event to take advantageof the saccade-masking phenomenon.

In addition to reconfiguring the video encoder 119, the encodingadjustment application 116 may be capable of reconfiguring theapplication 118 to conserve resources used in generating the videosignal. For example, the encoding adjustment application 116 mayconfigure the application 118 to generate a video signal with a lowerresolution, fewer colors, fewer rendered polygons, etc. In variousembodiments, the encoding adjustment application 116 may interface withone or more graphics libraries used by the application 118 (e.g.,DirectX®, etc.) to accomplish such an adjustment. Such an adjustment ofthe source video signal may also result in using fewer resources inencoding the source video signal.

The wrapper 121 corresponds to an application that provides avirtualized environment for execution of the application 118. Inparticular, the wrapper 121 may be configured to virtualize one or moreof the resources that the application 118 expects to access. Suchresources may include a keyboard, a mouse, a joystick, a video device, asound device, etc. In this way, the wrapper 121 is able to provide inputcommands to the application 118 as if the wrapper 121 emulates akeyboard, a mouse, or another type of input device.

Different types of wrappers 121 may be provided for differentapplications 118 or classes of applications 118. As non-limitingexamples, different wrappers 121 may be provided for applications 118using different application programming interfaces (APIs) such asOpenGL®, DirectX®, the Graphics Device Interface (GDI), and so on. Wherethe application 118 is configured for execution in a specialized videogame device or another type of computing device, the wrapper 121 mayinclude an emulation application that emulates the device. The wrapper121 may be configured to deliver the video signal generated by theapplication 118 to the video encoder 119 for encoding.

The application state information 124 that is maintained by the serverapplication 115 includes various data relating to application sessionsthat are currently active. For example, the application stateinformation 124 may track the users that are currently participating inthe application session, scores and status information associated withthe users, security permissions associated with the application session(e.g., who can or cannot join), and so on. In some embodiments, some orall of the application state information 124 may be discarded when anapplication session ends.

The data stored in the data store 112 includes, for example,applications 127, video encoders 129, wrappers 130, saved state data133, user data 136, saccadic event profiles 137, encoding adjustmentconfiguration data 138, and potentially other data. The applications 127correspond to a library of video games or other applications that areavailable to be launched as applications 118. The applications 127 maycorrespond to executable code within the computing device 103.Alternatively, the applications 127 may correspond to code that isexecutable within another type of device but is not executable withinthe computing device 103. Such applications 127 may be referred to as“binaries,” read-only memory images (ROMs), and other terms. Aparticular application 127 may be executed as multiple instances of theapplications 118 for multiple application sessions.

The video encoders 129 correspond to the various types of video encoders119 that may be employed in the computing device 103. Some videoencoders 129 may correspond to specific formats, such as, for example,H.264, MPEG-4, MPEG-2, 3D video streams, and/or other formats. Thewrappers 130 correspond to the executable code that implements thevarious types of wrappers 121. The wrappers 130 are executable in thecomputing device 103 and may be executed as multiple instances of thewrappers 121 for multiple application sessions.

The saved state data 133 corresponds to application states that havebeen saved by the applications 118. Because the applications 118 areexecuted in a virtualized environment, the applications 118 may writestate information to a virtual location, which is then mapped forstorage in the data store 112 as the saved state data 133. The savedstate data 133 may correspond to data saved normally by the application118 or may correspond to a memory image of the application 118 that maybe resumed at any time. The user data 136 includes various data relatedto the users of the applications 118, such as, for example, securitycredentials, application preferences, billing information, a listing ofother users that are permitted to join application sessions started bythe user, and so on.

The saccadic event profiles 137 include data that assists the encodingadjustment application 116 in detecting saccade-inducing events in videosignals. To this end, the saccadic event profiles 137 may includefingerprints that may be applied to frames of a video signal in order todetect the occurrence of a saccade-inducing event. As a non-limitingexample, an explosion in a certain application 118 may be understood tocause a saccade. Such an explosion may be associated with acharacteristic fireball graphic. A fingerprint of this graphic may bestored in the saccadic event profiles 137. The fingerprint may be laterused by the encoding adjustment application 116 to detect the saccadicevent based on the presence of the characteristic graphic in a videoframe.

Additionally, an application 118 may provide metadata regarding the gameplay represented in the video signal by way of an applicationprogramming interface (API). Such metadata may describe the occurrenceof an event in a video signal that may predicted to induce a saccade inthe user, e.g., explosions, sudden appearances of enemies, suddenchanges in lighting or contrast, and so on. The saccadic event profiles137 may describe indications of certain such events as saccade-inducingevents.

The encoding adjustment configuration data 138 includes variousconfigurations that may be applied to video encoders 119 and/orapplications 118. The encoding adjustment configuration data 138 mayinclude initial configurations and conservation configurations that areused to conserve resources associated with the video stream and/or videosignal. As a non-limiting example, an initial configuration may specifythat a video signal is to be encoded with an H.264 video encoder 129with a 1024×768 pixel resolution, at 60 frames per second, with 16 bitcolor, and at a 2.0 Megabit per second bitrate. As another non-limitingexample, a conservation configuration may specify that a portion of thevideo signal is to be encoded to be encoded with an H.264 video encoder129 with a 1024×768 pixel resolution, at 24 frames per second, with 8bit color, and at a 256 Kilobit per second bitrate. The resolution of aportion of the video signal may also change in the conservationconfiguration, though the portion of the video signal may be renderedwith the same size relative to the rest of the video signal.

The client 106 is representative of a plurality of client devices thatmay be coupled to the network 109. The clients 106 may be geographicallydiverse. The client 106 may comprise, for example, a processor-basedsystem such as a computer system. Such a computer system may be embodiedin the form of a desktop computer, a laptop computer, personal digitalassistants, cellular telephones, smartphones, set-top boxes, musicplayers, web pads, tablet computer systems, game consoles, electronicbook readers, or other devices with like capability.

The client 106 may include a display 139. The display 139 may comprise,for example, one or more devices such as cathode ray tubes (CRTs),liquid crystal display (LCD) screens, gas plasma-based flat paneldisplays, LCD projectors, or other types of display devices, etc. Theclient 106 may include one or more input devices 142. The input devices142 may comprise, for example, devices such as keyboards, mice,joysticks, accelerometers, light guns, game controllers, touch pads,touch sticks, push buttons, optical sensors, microphones, hapticdevices, webcams, and/or any other devices that can provide user input.

The client 106 may be configured to execute various applications such asa client application 145 and/or other applications. The clientapplication 145 is executed to allow a user to launch, join, play, andotherwise interact with an application 118 executed in the computingdevice 103. To this end, the client application 145 is configured tocapture input provided by the user through one or more of the inputdevices 142 and send this input over the network 109 to the computingdevice 103 as input data 122.

The client application 145 is also configured to obtain video data 123over the network 109 from the computing device 103 and render a screen148 on the display 139. To this end, the client application 145 mayinclude one or more video and audio players to play out a video streamgenerated by a video encoder 119. In one embodiment, the clientapplication 145 comprises a plug-in within a browser application. Theclient 106 may be configured to execute applications beyond the clientapplication 145 such as, for example, browser applications, emailapplications, instant message applications, and/or other applications.

Next, a general description of the operation of the various componentsof the networked environment 100 is provided. To begin, a user at aclient 106 sends a request to launch an application 118 to the serverapplication 115. The server application 115 obtains the correspondingapplication 127 and wrapper 130 from the data store 112. The serverapplication 115 then launches the application 118 in the correspondingwrapper 121. The server application 115 tracks the status of theapplication session within the application state information 124.

The wrapper 121 provides a virtualized environment for the application118 that virtualizes one or more resources of the computing device 103.Such resources may include exclusive resources, i.e., resources forwhich the application 118 requests exclusive access. For example, theapplication 118 may request full screen access from a video device,which is an exclusive resource because normally only one application canhave full screen access. Furthermore, the wrapper may virtualize inputdevices such as, for example, keyboards, mice, etc., which may notactually be present in the computing device 103. In various embodiments,the wrapper 121 may correspond to a virtual machine and/or the wrapper121 may be executed within a virtual machine.

The user at the client 106 enters input commands for the application 118by use of the input devices 142 of the client 106. As a non-limitingexample, the user may depress a left mouse button. Accordingly, theclient application 145 functions to encode the input command into aformat that may be transmitted over the network 109 within the inputdata 122. The server application 115 receives the input command andpasses it to the wrapper 121. The wrapper 121 then provides a left mousebutton depression to the application 118 by way of a virtualized mouse.In some embodiments, different input commands may be presented to theapplication 118 from those that were generated by a client 106. As anon-limiting example, if a user sends a mouse down command and theclient application 145 loses focus, the wrapper 121 may be configured tosend a mouse down command followed by a mouse up command. In variousembodiments, the input commands may be relayed to the wrapper 121 assoon as possible, or the input commands may be queued by the wrapper 121and relayed to the application 118 sequentially from the queue accordingto another approach.

Various embodiments enable input generated through one type of inputdevice 142 in a client 106 to be transformed by the wrapper 121 intoinput commands provided to the application 118 through an entirelydifferent type of virtual input device. As a non-limiting example, inputgenerated by an accelerometer in the client 106 may be translated by thewrapper 121 into input provided through a virtual mouse. Thus,completely different kinds of input devices 142 may be used in theapplication 118 that may not have been contemplated when the application118 was implemented.

Moreover, because the client 106 is decoupled from the hardwarerequirements of the application 118, the application 118 may be used ina diverse variety of clients 106 that are capable of streaming videowith acceptable bandwidth and latency over a network 109. For example,the application 118 may be used on a client 106 that is a smartphone.Thus, the client 106 need not include expensive graphics hardware toperform the complex three-dimensional rendering that may be necessary toexecute the application 118. By contrast, the hardware of the computingdevice 103 may be upgraded, as needed, to meet the hardware requirementsof the latest and most computationally intensive applications 118. Invarious embodiments, the video stream encoded by the video encoder 119may be scaled according to the bitrate and/or other characteristics ofthe connection between the computing device 103 and the client 106 overthe network 109.

The graphical output of the application 118 is captured by the wrapper121 and encoded into a video stream. Additionally, the audio output ofthe application 118 may be captured and multiplexed into the videostream. The video stream is transmitted by the server application 115 tothe client 106 over the network 109 as the video data 123. The clientapplication 145 obtains the video data 123 and plays it out on thedisplay 139 in a screen 148.

Turning now to FIGS. 2A-2C, shown are examples of user interfacesrendered by the client application 145 (FIG. 1) executed in the client106 (FIG. 1) in the networked environment 100 (FIG. 1). In particular,FIG. 2A depicts a screen 148 rendered on the display 139 (FIG. 1) from avideo stream. The screen 148 in FIG. 2A shows a sprite 203 that is beingcontrolled by the user. In some embodiments, it may be assumed by theencoding adjustment application 116 (FIG. 1) that the user is payingattention to the sprite 203 based on receipt of an input commandcontrolling the sprite 203.

In FIG. 2B, a saccadic event 206 occurs, which corresponds to anexplosion in the game environment. The encoding adjustment application116 may then determine that the attention of the user is directed to thesaccadic event 206. When the user moves from paying attention to thesprite 203 to the saccadic event 206, a saccade may occur in the user.Although the attention of the user moves from a sprite 203 to a saccadicevent 206, it is understood that the attention of the user may move fromanother saccadic event 206 to the saccadic event 206. Further, theattention of the user may move from an undetermined location on thescreen 148 to the saccadic event 206.

During and relative to a predicted saccade, the encoding adjustmentapplication 116 may configure the video encoder 119 (FIG. 1) to conserveresources associated with encoding the video stream where the user isnot likely to perceive quality problems. Such resources may includeprocessor time and/or memory consumed by the video encoder 119 and/orbandwidth on the network 109 (FIG. 1) consumed by the resulting videostream.

FIG. 2C shows a division of FIG. 2B into four regions 209 a, 209 b, 209c, and 209 d. The saccadic event 206 corresponds to a rapid change inregion 209 a. The sprite 203 is located in region 209 c. As theattention of the user is drawn from region 209 c to 209 a, the videoencoder 119 may be configured to encode regions 209 b, 209 c, and 209 dwith a lower quality to reduce resource consumption. Because the user ispredicted to experience a saccade, the user is unlikely to perceive thereduction in quality. Accordingly, the experience of the user in playingthe application 118 (FIG. 1) is not degraded.

Although the operation of the encoding adjustment application 116 isdescribed in relation to a video signal generated by an application 118,it is understood that principles of the present disclosure may beapplied to any other encoding of video signals into video streams. Forexample, explosions, changes in contrast, appearance of characters, etc.may occur in television programs, movies, and so on. Accordingly,various embodiments of the present disclosure may be able to recognizesaccadic events 206 in television programs, movies, etc. Moreover,various embodiments of the present disclosure may be able to detect userinattention regarding a video stream of television programs, movies,etc.

Referring next to FIG. 3, shown is a flowchart that provides one exampleof the operation of a portion of the encoding adjustment application 116according to various embodiments. It is understood that the flowchart ofFIG. 3 provides merely an example of the many different types offunctional arrangements that may be employed to implement the operationof the portion of the encoding adjustment application 116 as describedherein. As an alternative, the flowchart of FIG. 3 may be viewed asdepicting an example of steps of a method implemented in the computingdevice 103 (FIG. 1) according to one or more embodiments.

Beginning with box 303, the encoding adjustment application 116 detectsan event occurring in a region of a video signal. Specifically, theregion may correspond to a region in one or more frames of the videosignal. The encoding adjustment application 116 may detect the event byidentifying a rapid change in color, luminosity, and/or other videocharacteristics relative to previous frames of the video signal.Alternatively, the encoding adjustment application 116 may identify agraphical event in the video signal according to a fingerprint stored inthe saccadic event profiles 137 (FIG. 1). In some embodiments, theencoding adjustment application 116 may receive an indication from thecorresponding application 118 (FIG. 1) that an event is occurring.

In box 306, the encoding adjustment application 116 determines whetherthe event detected in box 303 is predicted to cause a saccade. Where theencoding adjustment application 116 obtains the indication that theevent is occurring from the application 118, the encoding adjustmentapplication 116 may correlate the indication with a saccadic event byusing data stored in the saccadic event profiles 137. Where the encodingadjustment application 116 detects a rapid change between frames, theencoding adjustment application 116 may refer to one or more thresholdsstored in the saccadic event profiles 137 to determine whether the rapidchange is likely to attract the attention of the user and induce asaccade.

If the encoding adjustment application 116 determines that the event isnot predicted to cause a saccade, the encoding adjustment application116 maintains the currently configured encoding of the video signal inbox 309. In other words, the event may not be significant enough or maynot be distinct enough from other action occurring in the video signalto attract the attention of the user to the event. It may also be thecase that the user may be predicted to have become accustomed to thespecific type of event due to location on the display 139 (FIG. 1),frequency of repetition, recent repetition, and/or other factors. If theuser is accustomed to the event, or if another event had just occurredin or near the same location, a saccade may be unlikely. Thereafter, theportion of the encoding adjustment application 116 ends.

Otherwise, if the encoding adjustment application 116 determines thatthe event is predicted to cause a saccade, the encoding adjustmentapplication 116 proceeds to box 312. In box 312, the encoding adjustmentapplication 116 adjusts the encoding of the video signal in the otherregions of the video frames to conserve resource usage. The encodingadjustment application 116 may configure the video encoder 119 (FIG. 1)to move from an initial state with an initial encoder configuration to aconservation state with a conservation encoder configuration.

Such configurations may be loaded from the encoding adjustmentconfiguration data 138 (FIG. 1). Such a conservation encoderconfiguration may result in lower memory usage, lower processor usage,lower network bandwidth usage, and/or other reductions in resourceconsumption associated with the video stream. In some embodiments, theentire video signal may be encoded in a lower quality during the timeperiod of the saccade to take advantage of saccadic masking while theeye is re-aimed from one position on the screen 148 (FIG. 1) to another.

Next, in box 315, the encoding adjustment application 116 determineswhether the saccade is completed. In other words, the encodingadjustment application 116 determines whether the user is predicted tobe focused on the region of the screen 148 that contains thesaccade-inducing event. If the user is focused on that area, the usermay then look at another area of the screen 148 at any time. If thesaccade has not completed, the encoding adjustment application 116returns to box 312 and maintains the adjusted encoding configuration ofthe video signal that conserves resources.

If the saccade has completed, the encoding adjustment application 116continues to box 318 and returns the encoding of the video signal to thepreviously configured encoding. Because the user may look at some otherarea of the screen 148, the encoding configuration of the video encoder119 may be readjusted to use the initial, higher-quality encodingconfiguration. Thereafter, the portion of the encoding adjustmentapplication 116 ends.

Moving on to FIG. 4, shown is a flowchart that provides one example ofthe operation of another portion of the encoding adjustment application116 according to various embodiments. It is understood that theflowchart of FIG. 4 provides merely an example of the many differenttypes of functional arrangements that may be employed to implement theoperation of the portion of the encoding adjustment application 116 asdescribed herein. As an alternative, the flowchart of FIG. 4 may beviewed as depicting an example of steps of a method implemented in thecomputing device 103 (FIG. 1) according to one or more embodiments.

Beginning with box 403, the encoding adjustment application 116 detectsuser inattention. As a non-limiting example, the user may be talking ontelephone, in another room, or otherwise not paying attention to thescreen 148 (FIG. 1). Accordingly, the user is not moving a mouse, nottyping on the keyboard, etc. Therefore, no input data 122 (FIG. 1) isobtained by the server application 115 (FIG. 1) when the user is notpaying attention to the screen 148. When a predetermined time periodelapses, the encoding adjustment application 116 may regard the user asidle and not paying attention. As another non-limiting example, if theuser minimizes the client application 145 (FIG. 1), the clientapplication 145 may be configured to send an indication of userinattention to the server application 115.

In box 404, the encoding adjustment application 116 determines whetheranother user participating in the game session is paying attention. Ifanother user is paying attention, the video stream encoding continuesunaffected, and the portion of the encoding adjustment application 116ends. However, if no other users are paying attention, the encodingadjustment application 116 proceeds to box 406.

In box 406, the encoding adjustment application 116 stops the encodingof the video signal into the video stream. In other embodiments, theencoding adjustment application 116 may instead configure the videoencoder 119 (FIG. 1) to encode the video signal into a lower qualityvideo stream. In either case, processing resources and/or networkresources may be conserved. Where the encoding is stopped completely,the video encoder 119 may be terminated, thereby freeing up memory ofthe computing device 103. However, the application 118 (FIG. 1) maycontinue to execute in the computing device 103 and generate the videosignal even though the corresponding video encoder 119 has beenterminated.

In box 409, the encoding adjustment application 116 determines whetherthe user has resumed paying attention to the screen 148. The user mayhave actuated an input device 142 (FIG. 1), thereby causing input data122 to be sent to the server application 115. Alternatively, the usermay have restored a client application 145 that had been minimized,thereby causing the client application 145 to send an indication ofvisibility to the computing device 103.

If the user has resumed paying attention, the encoding adjustmentapplication 116 continues to box 412 and restarts the encoding of thevideo signal into the video stream. In another embodiment, the encodingadjustment application 116 may reconfigure the video encoder 119 to usean initial configuration after employing a conservation configurationwhile the user was inattentive. If the video encoder 119 had beenterminated, a new instance of the video encoder 119 may be launched andconfigured to perform the encoding of the video signal into the videostream. Thereafter, the portion of the encoding adjustment application116 ends.

Otherwise, if the user does not resume paying attention, the encodingmay remain stopped or may continue according to the conservationconfiguration. If the encoding continues according to the conservationconfiguration, it may be stopped entirely after the expiration of atimeout period. Additionally, the application 118 and/or the wrapper 121(FIG. 1) may be stopped by the server after the expiration of a timeoutperiod. Thereafter, the portion of the encoding adjustment application116 ends.

With reference to FIG. 5, shown is a schematic block diagram of thecomputing device 103 according to an embodiment of the presentdisclosure. The computing device 103 includes at least one processorcircuit, for example, having a processor 503, a memory 506, and one ormore graphics devices 507, all of which are coupled to a local interface509. To this end, the computing device 103 may comprise, for example, atleast one server computer or like device. The local interface 509 maycomprise, for example, a data bus with an accompanying address/controlbus or other bus structure as can be appreciated. The graphics devices507 may correspond to high-performance graphics hardware, including oneor more graphics processors 512. Non-limiting examples of commerciallyavailable graphics processors 512 include the NVIDIA® Tesla series. Thegraphics devices 507 are configured to render graphics corresponding tothe applications 118 executed in the computing device 103.

Stored in the memory 506 are both data and several components that areexecutable by the processor 503. In particular, stored in the memory 506and executable by the processor 503 are the server application 115, theencoding adjustment application 116, the applications 118, the videoencoders 119, the wrappers 121, and potentially other applications. Alsostored in the memory 506 may be a data store 112 and other data. Inaddition, an operating system may be stored in the memory 506 andexecutable by the processor 503.

It is understood that there may be other applications that are stored inthe memory 506 and are executable by the processors 503 as can beappreciated. Where any component discussed herein is implemented in theform of software, any one of a number of programming languages may beemployed such as, for example, C, C++, C#, Objective C, Java®,JavaScript®, Perl, PHP, Visual Basic®, Python®, Ruby, Delphi®, Flash®,or other programming languages.

A number of software components are stored in the memory 506 and areexecutable by the processor 503. In this respect, the term “executable”means a program file that is in a form that can ultimately be run by theprocessor 503. Examples of executable programs may be, for example, acompiled program that can be translated into machine code in a formatthat can be loaded into a random access portion of the memory 506 andrun by the processor 503, source code that may be expressed in properformat such as object code that is capable of being loaded into a randomaccess portion of the memory 506 and executed by the processor 503, orsource code that may be interpreted by another executable program togenerate instructions in a random access portion of the memory 506 to beexecuted by the processor 503, etc. An executable program may be storedin any portion or component of the memory 506 including, for example,random access memory (RAM), read-only memory (ROM), hard drive,solid-state drive, USB flash drive, memory card, optical disc such ascompact disc (CD) or digital versatile disc (DVD), floppy disk, magnetictape, or other memory components.

The memory 506 is defined herein as including both volatile andnonvolatile memory and data storage components. Volatile components arethose that do not retain data values upon loss of power. Nonvolatilecomponents are those that retain data upon a loss of power. Thus, thememory 506 may comprise, for example, random access memory (RAM),read-only memory (ROM), hard disk drives, solid-state drives, USB flashdrives, memory cards accessed via a memory card reader, floppy disksaccessed via an associated floppy disk drive, optical discs accessed viaan optical disc drive, magnetic tapes accessed via an appropriate tapedrive, and/or other memory components, or a combination of any two ormore of these memory components. In addition, the RAM may comprise, forexample, static random access memory (SRAM), dynamic random accessmemory (DRAM), or magnetic random access memory (MRAM) and other suchdevices. The ROM may comprise, for example, a programmable read-onlymemory (PROM), an erasable programmable read-only memory (EPROM), anelectrically erasable programmable read-only memory (EEPROM), or otherlike memory device.

Also, the processor 503 may represent multiple processors 503 and thememory 506 may represent multiple memories 506 that operate in parallelprocessing circuits, respectively. In such a case, the local interface509 may be an appropriate network 109 (FIG. 1) that facilitatescommunication between any two of the multiple processors 503, betweenany processor 503 and any of the memories 506, or between any two of thememories 506, etc. The local interface 509 may comprise additionalsystems designed to coordinate this communication, including, forexample, performing load balancing. The processor 503 may be ofelectrical or of some other available construction.

Although the server application 115, the encoding adjustment application116, the applications 118, the video encoders 119, the wrappers 121, andother various systems described herein may be embodied in software orcode executed by general purpose hardware as discussed above, as analternative the same may also be embodied in dedicated hardware or acombination of software/general purpose hardware and dedicated hardware.If embodied in dedicated hardware, each can be implemented as a circuitor state machine that employs any one of or a combination of a number oftechnologies. These technologies may include, but are not limited to,discrete logic circuits having logic gates for implementing variouslogic functions upon an application of one or more data signals,application specific integrated circuits having appropriate logic gates,or other components, etc. Such technologies are generally well known bythose skilled in the art and, consequently, are not described in detailherein.

The flowcharts of FIGS. 3 and 4 show the functionality and operation ofan implementation of portions of the encoding adjustment application116. If embodied in software, each block may represent a module,segment, or portion of code that comprises program instructions toimplement the specified logical function(s). The program instructionsmay be embodied in the form of source code that comprises human-readablestatements written in a programming language or machine code thatcomprises numerical instructions recognizable by a suitable executionsystem such as a processor 503 in a computer system or other system. Themachine code may be converted from the source code, etc. If embodied inhardware, each block may represent a circuit or a number ofinterconnected circuits to implement the specified logical function(s).

Although the flowcharts of FIGS. 3 and 4 show a specific order ofexecution, it is understood that the order of execution may differ fromthat which is depicted. For example, the order of execution of two ormore blocks may be scrambled relative to the order shown. Also, two ormore blocks shown in succession in FIGS. 3 and 4 may be executedconcurrently or with partial concurrence. Further, in some embodiments,one or more of the blocks shown in FIGS. 3 and 4 may be skipped oromitted. In addition, any number of counters, state variables, warningsemaphores, or messages might be added to the logical flow describedherein, for purposes of enhanced utility, accounting, performancemeasurement, or providing troubleshooting aids, etc. It is understoodthat all such variations are within the scope of the present disclosure.

Also, any logic or application described herein, including the serverapplication 115, the encoding adjustment application 116, theapplications 118, the video encoders 119, and the wrappers 121, thatcomprises software or code can be embodied in any non-transitorycomputer-readable medium for use by or in connection with an instructionexecution system such as, for example, a processor 503 in a computersystem or other system. In this sense, the logic may comprise, forexample, statements including instructions and declarations that can befetched from the computer-readable medium and executed by theinstruction execution system. In the context of the present disclosure,a “computer-readable medium” can be any medium that can contain, store,or maintain the logic or application described herein for use by or inconnection with the instruction execution system.

The computer-readable medium can comprise any one of many physical mediasuch as, for example, magnetic, optical, or semiconductor media. Morespecific examples of a suitable computer-readable medium would include,but are not limited to, magnetic tapes, magnetic floppy diskettes,magnetic hard drives, memory cards, solid-state drives, USB flashdrives, or optical discs. Also, the computer-readable medium may be arandom access memory (RAM) including, for example, static random accessmemory (SRAM) and dynamic random access memory (DRAM), or magneticrandom access memory (MRAM). In addition, the computer-readable mediummay be a read-only memory (ROM), a programmable read-only memory (PROM),an erasable programmable read-only memory (EPROM), an electricallyerasable programmable read-only memory (EEPROM), or other type of memorydevice.

It should be emphasized that the above-described embodiments of thepresent disclosure are merely possible examples of implementations setforth for a clear understanding of the principles of the disclosure.Many variations and modifications may be made to the above-describedembodiment(s) without departing substantially from the spirit andprinciples of the disclosure. All such modifications and variations areintended to be included herein within the scope of this disclosure andprotected by the following claims.

1-11. (canceled)
 12. A method, comprising: predicting, by at least one computing device, a temporary lapse of attention by a user to a video stream; adjusting, by the at least one computing device, an encoding of the video stream from an initial state to a conservation state in response to predicting the temporary lapse of attention; and wherein the conservation state is configured to conserve at least one resource used for the encoding of the video stream relative to the initial state.
 13. The method of claim 12, wherein predicting the temporary lapse of attention further comprises detecting, by the at least one computing device, that the user is not paying attention to the video stream.
 14. The method of claim 12, further comprising encoding, by the at least one computing device, a video signal generated by an interactive application into the video stream.
 15. The method of claim 14, wherein the interactive application comprises a game application that is executed by the at least one computing device, and the user interacts with the game application by sending at least one input to the game application over a data communications network.
 16. The method of claim 14, wherein predicting the temporary lapse of attention further comprises determining, by the at least one computing device, that the interactive application has not obtained an input from the user in at least a predetermined time period.
 17. The method of claim 14, wherein adjusting the encoding further comprises reconfiguring, by the at least one computing device, the interactive application to conserve at least one resource used in generating the video signal.
 18. The method of claim 12, wherein adjusting the encoding further comprises stopping, by the at least one computing device, the encoding of a video signal into the video stream.
 19. The method of claim 12, wherein adjusting the encoding further comprises reconfiguring, by the at least one computing device, a video encoder that performs the encoding to use a first encoding configuration that is associated with a lower quality video stream than a second encoding configuration that is used in the initial state.
 20. The method of claim 12, further comprising: predicting, by the at least one computing device, that the temporary lapse of attention has ended; and readjusting, by the at least one computing device, the encoding of the video stream from the conservation state to the initial state in response to predicting that the temporary lapse of attention has ended.
 21. The method of claim 20, wherein predicting that the temporary lapse of attention has ended further comprises determining, by the at least one computing device, that an interactive application has obtained at least one input from the user.
 22. The method of claim 20, wherein readjusting the encoding further comprises restarting, by the at least one computing device, a stopped encoding of the video stream.
 23. The method of claim 20, wherein readjusting the encoding further comprises reconfiguring, by the at least one computing device, a video encoder that performs the encoding to use an encoding configuration associated with the initial state.
 24. A system, comprising: at least one computing device; and at least one application executed in the at least one computing device, the at least one application comprising: logic configured to predict a temporary lapse of attention by a user to a video stream, the video stream including a video signal generated by an interactive application; logic configured to adjust an encoding of the video stream from an initial state to a conservation state in response to predicting the temporary lapse of attention; and wherein the conservation state is configured to conserve at least one resource used for the encoding of the video stream relative to the initial state.
 25. The system of claim 24, wherein the logic configured to predict the temporary lapse of attention by the user to the video stream further comprises logic configured to receive an indication that the user is idle from a client device configured to render the video stream.
 26. The system of claim 24, wherein the logic configured to predict the temporary lapse of attention by the user to the video stream further comprises logic configured to predict that an attention of the user is drawn to a saccadic event.
 27. The system of claim 24, wherein the logic configured to predict the temporary lapse of attention by the user to the video stream further comprises logic configured to determine that input from the user is not received for at least a predetermined time period.
 28. A non-transitory computer-readable medium embodying a program executable by at least one computing device, comprising: code configured to encode a video signal generated by an interactive application into a video stream; code configured to send the video stream to a plurality of client devices corresponding to a plurality of users; code configured to predict a temporary lapse of attention by all of the plurality of users to the video stream; code configured to adjust an encoding of the video stream from an initial state to a conservation state in response to predicting the temporary lapse of attention; and wherein the conservation state is configured to conserve at least one resource used for the encoding of the video stream relative to the initial state.
 29. The non-transitory computer-readable medium of claim 28, wherein the plurality of users are participants in a session of the interactive application.
 30. The non-transitory computer-readable medium of claim 28, wherein, as compared to the initial state, the conservation state is associated with at least one of: a lower resolution, a lower frame rate, a lower bitrate, or a lower color depth.
 31. The non-transitory computer-readable medium of claim 28, wherein the code configured to predict the temporary lapse of attention further comprises code configured to determine that the interactive application has not obtained an input from any of the plurality of users in at least a predetermined time period. 